Commit 6890acac authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull objtool fixes from Borislav Petkov:

 - Update section headers before the respective relocations to not
   trigger a safety check in elftoolchain's implementation of libelf

 - Do not add garbage data to the .rela.orc_unwind_ip section

* tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Update section header before relocations
  objtool: Check for gelf_update_rel[a] failures
parents f644750c 86e1e054

tools/objtool/elf.c

+25 −31
Original line number Diff line number Diff line
@@ -508,6 +508,7 @@ int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset, 
	list_add_tail(&reloc->list, &sec->reloc->reloc_list);

	elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));



	sec->reloc->sh.sh_size += sec->reloc->sh.sh_entsize;

	sec->reloc->changed = true;



	return 0;
@@ -977,63 +978,63 @@ static struct section *elf_create_reloc_section(struct elf *elf, 
	}

}



static int elf_rebuild_rel_reloc_section(struct section *sec, int nr)

static int elf_rebuild_rel_reloc_section(struct section *sec)

{

	struct reloc *reloc;

	int idx = 0, size;

	int idx = 0;

	void *buf;



	/* Allocate a buffer for relocations */

	size = nr * sizeof(GElf_Rel);

	buf = malloc(size);

	buf = malloc(sec->sh.sh_size);

	if (!buf) {

		perror("malloc");

		return -1;

	}



	sec->data->d_buf = buf;

	sec->data->d_size = size;

	sec->data->d_size = sec->sh.sh_size;

	sec->data->d_type = ELF_T_REL;



	sec->sh.sh_size = size;



	idx = 0;

	list_for_each_entry(reloc, &sec->reloc_list, list) {

		reloc->rel.r_offset = reloc->offset;

		reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);

		gelf_update_rel(sec->data, idx, &reloc->rel);

		if (!gelf_update_rel(sec->data, idx, &reloc->rel)) {

			WARN_ELF("gelf_update_rel");

			return -1;

		}

		idx++;

	}



	return 0;

}



static int elf_rebuild_rela_reloc_section(struct section *sec, int nr)

static int elf_rebuild_rela_reloc_section(struct section *sec)

{

	struct reloc *reloc;

	int idx = 0, size;

	int idx = 0;

	void *buf;



	/* Allocate a buffer for relocations with addends */

	size = nr * sizeof(GElf_Rela);

	buf = malloc(size);

	buf = malloc(sec->sh.sh_size);

	if (!buf) {

		perror("malloc");

		return -1;

	}



	sec->data->d_buf = buf;

	sec->data->d_size = size;

	sec->data->d_size = sec->sh.sh_size;

	sec->data->d_type = ELF_T_RELA;



	sec->sh.sh_size = size;



	idx = 0;

	list_for_each_entry(reloc, &sec->reloc_list, list) {

		reloc->rela.r_offset = reloc->offset;

		reloc->rela.r_addend = reloc->addend;

		reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);

		gelf_update_rela(sec->data, idx, &reloc->rela);

		if (!gelf_update_rela(sec->data, idx, &reloc->rela)) {

			WARN_ELF("gelf_update_rela");

			return -1;

		}

		idx++;

	}
@@ -1042,16 +1043,9 @@ static int elf_rebuild_rela_reloc_section(struct section *sec, int nr) 


static int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)

{

	struct reloc *reloc;

	int nr;



	nr = 0;

	list_for_each_entry(reloc, &sec->reloc_list, list)

		nr++;



	switch (sec->sh.sh_type) {

	case SHT_REL:  return elf_rebuild_rel_reloc_section(sec, nr);

	case SHT_RELA: return elf_rebuild_rela_reloc_section(sec, nr);

	case SHT_REL:  return elf_rebuild_rel_reloc_section(sec);

	case SHT_RELA: return elf_rebuild_rela_reloc_section(sec);

	default:       return -1;

	}

}
@@ -1111,12 +1105,6 @@ int elf_write(struct elf *elf) 
	/* Update changed relocation sections and section headers: */

	list_for_each_entry(sec, &elf->sections, list) {

		if (sec->changed) {

			if (sec->base &&

			    elf_rebuild_reloc_section(elf, sec)) {

				WARN("elf_rebuild_reloc_section");

				return -1;

			}



			s = elf_getscn(elf->elf, sec->idx);

			if (!s) {

				WARN_ELF("elf_getscn");
@@ -1127,6 +1115,12 @@ int elf_write(struct elf *elf) 
				return -1;

			}



			if (sec->base &&

			    elf_rebuild_reloc_section(elf, sec)) {

				WARN("elf_rebuild_reloc_section");

				return -1;

			}



			sec->changed = false;

			elf->changed = true;

		}